Loading...
Note: File does not exist in v3.1.
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Azoteq IQS550/572/525 Trackpad/Touchscreen Controller
4 *
5 * Copyright (C) 2018
6 * Author: Jeff LaBundy <jeff@labundy.com>
7 *
8 * These devices require firmware exported from a PC-based configuration tool
9 * made available by the vendor. Firmware files may be pushed to the device's
10 * nonvolatile memory by writing the filename to the 'fw_file' sysfs control.
11 *
12 * Link to PC-based configuration tool and data sheet: http://www.azoteq.com/
13 */
14
15#include <linux/delay.h>
16#include <linux/device.h>
17#include <linux/err.h>
18#include <linux/firmware.h>
19#include <linux/gpio/consumer.h>
20#include <linux/i2c.h>
21#include <linux/input.h>
22#include <linux/input/mt.h>
23#include <linux/input/touchscreen.h>
24#include <linux/interrupt.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/of_device.h>
28#include <linux/slab.h>
29#include <asm/unaligned.h>
30
31#define IQS5XX_FW_FILE_LEN 64
32#define IQS5XX_NUM_RETRIES 10
33#define IQS5XX_NUM_POINTS 256
34#define IQS5XX_NUM_CONTACTS 5
35#define IQS5XX_WR_BYTES_MAX 2
36
37#define IQS5XX_PROD_NUM_IQS550 40
38#define IQS5XX_PROD_NUM_IQS572 58
39#define IQS5XX_PROD_NUM_IQS525 52
40#define IQS5XX_PROJ_NUM_A000 0
41#define IQS5XX_PROJ_NUM_B000 15
42#define IQS5XX_MAJOR_VER_MIN 2
43
44#define IQS5XX_RESUME 0x00
45#define IQS5XX_SUSPEND 0x01
46
47#define IQS5XX_SW_INPUT_EVENT 0x10
48#define IQS5XX_SETUP_COMPLETE 0x40
49#define IQS5XX_EVENT_MODE 0x01
50#define IQS5XX_TP_EVENT 0x04
51
52#define IQS5XX_FLIP_X 0x01
53#define IQS5XX_FLIP_Y 0x02
54#define IQS5XX_SWITCH_XY_AXIS 0x04
55
56#define IQS5XX_PROD_NUM 0x0000
57#define IQS5XX_ABS_X 0x0016
58#define IQS5XX_ABS_Y 0x0018
59#define IQS5XX_SYS_CTRL0 0x0431
60#define IQS5XX_SYS_CTRL1 0x0432
61#define IQS5XX_SYS_CFG0 0x058E
62#define IQS5XX_SYS_CFG1 0x058F
63#define IQS5XX_TOTAL_RX 0x063D
64#define IQS5XX_TOTAL_TX 0x063E
65#define IQS5XX_XY_CFG0 0x0669
66#define IQS5XX_X_RES 0x066E
67#define IQS5XX_Y_RES 0x0670
68#define IQS5XX_CHKSM 0x83C0
69#define IQS5XX_APP 0x8400
70#define IQS5XX_CSTM 0xBE00
71#define IQS5XX_PMAP_END 0xBFFF
72#define IQS5XX_END_COMM 0xEEEE
73
74#define IQS5XX_CHKSM_LEN (IQS5XX_APP - IQS5XX_CHKSM)
75#define IQS5XX_APP_LEN (IQS5XX_CSTM - IQS5XX_APP)
76#define IQS5XX_CSTM_LEN (IQS5XX_PMAP_END + 1 - IQS5XX_CSTM)
77#define IQS5XX_PMAP_LEN (IQS5XX_PMAP_END + 1 - IQS5XX_CHKSM)
78
79#define IQS5XX_REC_HDR_LEN 4
80#define IQS5XX_REC_LEN_MAX 255
81#define IQS5XX_REC_TYPE_DATA 0x00
82#define IQS5XX_REC_TYPE_EOF 0x01
83
84#define IQS5XX_BL_ADDR_MASK 0x40
85#define IQS5XX_BL_CMD_VER 0x00
86#define IQS5XX_BL_CMD_READ 0x01
87#define IQS5XX_BL_CMD_EXEC 0x02
88#define IQS5XX_BL_CMD_CRC 0x03
89#define IQS5XX_BL_BLK_LEN_MAX 64
90#define IQS5XX_BL_ID 0x0200
91#define IQS5XX_BL_STATUS_RESET 0x00
92#define IQS5XX_BL_STATUS_AVAIL 0xA5
93#define IQS5XX_BL_STATUS_NONE 0xEE
94#define IQS5XX_BL_CRC_PASS 0x00
95#define IQS5XX_BL_CRC_FAIL 0x01
96#define IQS5XX_BL_ATTEMPTS 3
97
98struct iqs5xx_private {
99 struct i2c_client *client;
100 struct input_dev *input;
101 struct gpio_desc *reset_gpio;
102 struct mutex lock;
103 u8 bl_status;
104};
105
106struct iqs5xx_dev_id_info {
107 __be16 prod_num;
108 __be16 proj_num;
109 u8 major_ver;
110 u8 minor_ver;
111 u8 bl_status;
112} __packed;
113
114struct iqs5xx_ihex_rec {
115 char start;
116 char len[2];
117 char addr[4];
118 char type[2];
119 char data[2];
120} __packed;
121
122struct iqs5xx_touch_data {
123 __be16 abs_x;
124 __be16 abs_y;
125 __be16 strength;
126 u8 area;
127} __packed;
128
129static int iqs5xx_read_burst(struct i2c_client *client,
130 u16 reg, void *val, u16 len)
131{
132 __be16 reg_buf = cpu_to_be16(reg);
133 int ret, i;
134 struct i2c_msg msg[] = {
135 {
136 .addr = client->addr,
137 .flags = 0,
138 .len = sizeof(reg_buf),
139 .buf = (u8 *)®_buf,
140 },
141 {
142 .addr = client->addr,
143 .flags = I2C_M_RD,
144 .len = len,
145 .buf = (u8 *)val,
146 },
147 };
148
149 /*
150 * The first addressing attempt outside of a communication window fails
151 * and must be retried, after which the device clock stretches until it
152 * is available.
153 */
154 for (i = 0; i < IQS5XX_NUM_RETRIES; i++) {
155 ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
156 if (ret == ARRAY_SIZE(msg))
157 return 0;
158
159 usleep_range(200, 300);
160 }
161
162 if (ret >= 0)
163 ret = -EIO;
164
165 dev_err(&client->dev, "Failed to read from address 0x%04X: %d\n",
166 reg, ret);
167
168 return ret;
169}
170
171static int iqs5xx_read_word(struct i2c_client *client, u16 reg, u16 *val)
172{
173 __be16 val_buf;
174 int error;
175
176 error = iqs5xx_read_burst(client, reg, &val_buf, sizeof(val_buf));
177 if (error)
178 return error;
179
180 *val = be16_to_cpu(val_buf);
181
182 return 0;
183}
184
185static int iqs5xx_read_byte(struct i2c_client *client, u16 reg, u8 *val)
186{
187 return iqs5xx_read_burst(client, reg, val, sizeof(*val));
188}
189
190static int iqs5xx_write_burst(struct i2c_client *client,
191 u16 reg, const void *val, u16 len)
192{
193 int ret, i;
194 u16 mlen = sizeof(reg) + len;
195 u8 mbuf[sizeof(reg) + IQS5XX_WR_BYTES_MAX];
196
197 if (len > IQS5XX_WR_BYTES_MAX)
198 return -EINVAL;
199
200 put_unaligned_be16(reg, mbuf);
201 memcpy(mbuf + sizeof(reg), val, len);
202
203 /*
204 * The first addressing attempt outside of a communication window fails
205 * and must be retried, after which the device clock stretches until it
206 * is available.
207 */
208 for (i = 0; i < IQS5XX_NUM_RETRIES; i++) {
209 ret = i2c_master_send(client, mbuf, mlen);
210 if (ret == mlen)
211 return 0;
212
213 usleep_range(200, 300);
214 }
215
216 if (ret >= 0)
217 ret = -EIO;
218
219 dev_err(&client->dev, "Failed to write to address 0x%04X: %d\n",
220 reg, ret);
221
222 return ret;
223}
224
225static int iqs5xx_write_word(struct i2c_client *client, u16 reg, u16 val)
226{
227 __be16 val_buf = cpu_to_be16(val);
228
229 return iqs5xx_write_burst(client, reg, &val_buf, sizeof(val_buf));
230}
231
232static int iqs5xx_write_byte(struct i2c_client *client, u16 reg, u8 val)
233{
234 return iqs5xx_write_burst(client, reg, &val, sizeof(val));
235}
236
237static void iqs5xx_reset(struct i2c_client *client)
238{
239 struct iqs5xx_private *iqs5xx = i2c_get_clientdata(client);
240
241 gpiod_set_value_cansleep(iqs5xx->reset_gpio, 1);
242 usleep_range(200, 300);
243
244 gpiod_set_value_cansleep(iqs5xx->reset_gpio, 0);
245}
246
247static int iqs5xx_bl_cmd(struct i2c_client *client, u8 bl_cmd, u16 bl_addr)
248{
249 struct i2c_msg msg;
250 int ret;
251 u8 mbuf[sizeof(bl_cmd) + sizeof(bl_addr)];
252
253 msg.addr = client->addr ^ IQS5XX_BL_ADDR_MASK;
254 msg.flags = 0;
255 msg.len = sizeof(bl_cmd);
256 msg.buf = mbuf;
257
258 *mbuf = bl_cmd;
259
260 switch (bl_cmd) {
261 case IQS5XX_BL_CMD_VER:
262 case IQS5XX_BL_CMD_CRC:
263 case IQS5XX_BL_CMD_EXEC:
264 break;
265 case IQS5XX_BL_CMD_READ:
266 msg.len += sizeof(bl_addr);
267 put_unaligned_be16(bl_addr, mbuf + sizeof(bl_cmd));
268 break;
269 default:
270 return -EINVAL;
271 }
272
273 ret = i2c_transfer(client->adapter, &msg, 1);
274 if (ret != 1)
275 goto msg_fail;
276
277 switch (bl_cmd) {
278 case IQS5XX_BL_CMD_VER:
279 msg.len = sizeof(u16);
280 break;
281 case IQS5XX_BL_CMD_CRC:
282 msg.len = sizeof(u8);
283 /*
284 * This delay saves the bus controller the trouble of having to
285 * tolerate a relatively long clock-stretching period while the
286 * CRC is calculated.
287 */
288 msleep(50);
289 break;
290 case IQS5XX_BL_CMD_EXEC:
291 usleep_range(10000, 10100);
292 /* fall through */
293 default:
294 return 0;
295 }
296
297 msg.flags = I2C_M_RD;
298
299 ret = i2c_transfer(client->adapter, &msg, 1);
300 if (ret != 1)
301 goto msg_fail;
302
303 if (bl_cmd == IQS5XX_BL_CMD_VER &&
304 get_unaligned_be16(mbuf) != IQS5XX_BL_ID) {
305 dev_err(&client->dev, "Unrecognized bootloader ID: 0x%04X\n",
306 get_unaligned_be16(mbuf));
307 return -EINVAL;
308 }
309
310 if (bl_cmd == IQS5XX_BL_CMD_CRC && *mbuf != IQS5XX_BL_CRC_PASS) {
311 dev_err(&client->dev, "Bootloader CRC failed\n");
312 return -EIO;
313 }
314
315 return 0;
316
317msg_fail:
318 if (ret >= 0)
319 ret = -EIO;
320
321 if (bl_cmd != IQS5XX_BL_CMD_VER)
322 dev_err(&client->dev,
323 "Unsuccessful bootloader command 0x%02X: %d\n",
324 bl_cmd, ret);
325
326 return ret;
327}
328
329static int iqs5xx_bl_open(struct i2c_client *client)
330{
331 int error, i, j;
332
333 /*
334 * The device opens a bootloader polling window for 2 ms following the
335 * release of reset. If the host cannot establish communication during
336 * this time frame, it must cycle reset again.
337 */
338 for (i = 0; i < IQS5XX_BL_ATTEMPTS; i++) {
339 iqs5xx_reset(client);
340
341 for (j = 0; j < IQS5XX_NUM_RETRIES; j++) {
342 error = iqs5xx_bl_cmd(client, IQS5XX_BL_CMD_VER, 0);
343 if (!error || error == -EINVAL)
344 return error;
345 }
346 }
347
348 dev_err(&client->dev, "Failed to open bootloader: %d\n", error);
349
350 return error;
351}
352
353static int iqs5xx_bl_write(struct i2c_client *client,
354 u16 bl_addr, u8 *pmap_data, u16 pmap_len)
355{
356 struct i2c_msg msg;
357 int ret, i;
358 u8 mbuf[sizeof(bl_addr) + IQS5XX_BL_BLK_LEN_MAX];
359
360 if (pmap_len % IQS5XX_BL_BLK_LEN_MAX)
361 return -EINVAL;
362
363 msg.addr = client->addr ^ IQS5XX_BL_ADDR_MASK;
364 msg.flags = 0;
365 msg.len = sizeof(mbuf);
366 msg.buf = mbuf;
367
368 for (i = 0; i < pmap_len; i += IQS5XX_BL_BLK_LEN_MAX) {
369 put_unaligned_be16(bl_addr + i, mbuf);
370 memcpy(mbuf + sizeof(bl_addr), pmap_data + i,
371 sizeof(mbuf) - sizeof(bl_addr));
372
373 ret = i2c_transfer(client->adapter, &msg, 1);
374 if (ret != 1)
375 goto msg_fail;
376
377 usleep_range(10000, 10100);
378 }
379
380 return 0;
381
382msg_fail:
383 if (ret >= 0)
384 ret = -EIO;
385
386 dev_err(&client->dev, "Failed to write block at address 0x%04X: %d\n",
387 bl_addr + i, ret);
388
389 return ret;
390}
391
392static int iqs5xx_bl_verify(struct i2c_client *client,
393 u16 bl_addr, u8 *pmap_data, u16 pmap_len)
394{
395 struct i2c_msg msg;
396 int ret, i;
397 u8 bl_data[IQS5XX_BL_BLK_LEN_MAX];
398
399 if (pmap_len % IQS5XX_BL_BLK_LEN_MAX)
400 return -EINVAL;
401
402 msg.addr = client->addr ^ IQS5XX_BL_ADDR_MASK;
403 msg.flags = I2C_M_RD;
404 msg.len = sizeof(bl_data);
405 msg.buf = bl_data;
406
407 for (i = 0; i < pmap_len; i += IQS5XX_BL_BLK_LEN_MAX) {
408 ret = iqs5xx_bl_cmd(client, IQS5XX_BL_CMD_READ, bl_addr + i);
409 if (ret)
410 return ret;
411
412 ret = i2c_transfer(client->adapter, &msg, 1);
413 if (ret != 1)
414 goto msg_fail;
415
416 if (memcmp(bl_data, pmap_data + i, sizeof(bl_data))) {
417 dev_err(&client->dev,
418 "Failed to verify block at address 0x%04X\n",
419 bl_addr + i);
420 return -EIO;
421 }
422 }
423
424 return 0;
425
426msg_fail:
427 if (ret >= 0)
428 ret = -EIO;
429
430 dev_err(&client->dev, "Failed to read block at address 0x%04X: %d\n",
431 bl_addr + i, ret);
432
433 return ret;
434}
435
436static int iqs5xx_set_state(struct i2c_client *client, u8 state)
437{
438 struct iqs5xx_private *iqs5xx = i2c_get_clientdata(client);
439 int error1, error2;
440
441 if (iqs5xx->bl_status == IQS5XX_BL_STATUS_RESET)
442 return 0;
443
444 mutex_lock(&iqs5xx->lock);
445
446 /*
447 * Addressing the device outside of a communication window prompts it
448 * to assert the RDY output, so disable the interrupt line to prevent
449 * the handler from servicing a false interrupt.
450 */
451 disable_irq(client->irq);
452
453 error1 = iqs5xx_write_byte(client, IQS5XX_SYS_CTRL1, state);
454 error2 = iqs5xx_write_byte(client, IQS5XX_END_COMM, 0);
455
456 usleep_range(50, 100);
457 enable_irq(client->irq);
458
459 mutex_unlock(&iqs5xx->lock);
460
461 if (error1)
462 return error1;
463
464 return error2;
465}
466
467static int iqs5xx_open(struct input_dev *input)
468{
469 struct iqs5xx_private *iqs5xx = input_get_drvdata(input);
470
471 return iqs5xx_set_state(iqs5xx->client, IQS5XX_RESUME);
472}
473
474static void iqs5xx_close(struct input_dev *input)
475{
476 struct iqs5xx_private *iqs5xx = input_get_drvdata(input);
477
478 iqs5xx_set_state(iqs5xx->client, IQS5XX_SUSPEND);
479}
480
481static int iqs5xx_axis_init(struct i2c_client *client)
482{
483 struct iqs5xx_private *iqs5xx = i2c_get_clientdata(client);
484 struct touchscreen_properties prop;
485 struct input_dev *input;
486 int error;
487 u16 max_x, max_x_hw;
488 u16 max_y, max_y_hw;
489 u8 val;
490
491 if (!iqs5xx->input) {
492 input = devm_input_allocate_device(&client->dev);
493 if (!input)
494 return -ENOMEM;
495
496 input->name = client->name;
497 input->id.bustype = BUS_I2C;
498 input->open = iqs5xx_open;
499 input->close = iqs5xx_close;
500
501 input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
502 input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
503 input_set_capability(input, EV_ABS, ABS_MT_PRESSURE);
504
505 input_set_drvdata(input, iqs5xx);
506 iqs5xx->input = input;
507 }
508
509 touchscreen_parse_properties(iqs5xx->input, true, &prop);
510
511 error = iqs5xx_read_byte(client, IQS5XX_TOTAL_RX, &val);
512 if (error)
513 return error;
514 max_x_hw = (val - 1) * IQS5XX_NUM_POINTS;
515
516 error = iqs5xx_read_byte(client, IQS5XX_TOTAL_TX, &val);
517 if (error)
518 return error;
519 max_y_hw = (val - 1) * IQS5XX_NUM_POINTS;
520
521 error = iqs5xx_read_byte(client, IQS5XX_XY_CFG0, &val);
522 if (error)
523 return error;
524
525 if (val & IQS5XX_SWITCH_XY_AXIS)
526 swap(max_x_hw, max_y_hw);
527
528 if (prop.swap_x_y)
529 val ^= IQS5XX_SWITCH_XY_AXIS;
530
531 if (prop.invert_x)
532 val ^= prop.swap_x_y ? IQS5XX_FLIP_Y : IQS5XX_FLIP_X;
533
534 if (prop.invert_y)
535 val ^= prop.swap_x_y ? IQS5XX_FLIP_X : IQS5XX_FLIP_Y;
536
537 error = iqs5xx_write_byte(client, IQS5XX_XY_CFG0, val);
538 if (error)
539 return error;
540
541 if (prop.max_x > max_x_hw) {
542 dev_err(&client->dev, "Invalid maximum x-coordinate: %u > %u\n",
543 prop.max_x, max_x_hw);
544 return -EINVAL;
545 } else if (prop.max_x == 0) {
546 error = iqs5xx_read_word(client, IQS5XX_X_RES, &max_x);
547 if (error)
548 return error;
549
550 input_abs_set_max(iqs5xx->input,
551 prop.swap_x_y ? ABS_MT_POSITION_Y :
552 ABS_MT_POSITION_X,
553 max_x);
554 } else {
555 max_x = (u16)prop.max_x;
556 }
557
558 if (prop.max_y > max_y_hw) {
559 dev_err(&client->dev, "Invalid maximum y-coordinate: %u > %u\n",
560 prop.max_y, max_y_hw);
561 return -EINVAL;
562 } else if (prop.max_y == 0) {
563 error = iqs5xx_read_word(client, IQS5XX_Y_RES, &max_y);
564 if (error)
565 return error;
566
567 input_abs_set_max(iqs5xx->input,
568 prop.swap_x_y ? ABS_MT_POSITION_X :
569 ABS_MT_POSITION_Y,
570 max_y);
571 } else {
572 max_y = (u16)prop.max_y;
573 }
574
575 /*
576 * Write horizontal and vertical resolution to the device in case its
577 * original defaults were overridden or swapped as per the properties
578 * specified in the device tree.
579 */
580 error = iqs5xx_write_word(client,
581 prop.swap_x_y ? IQS5XX_Y_RES : IQS5XX_X_RES,
582 max_x);
583 if (error)
584 return error;
585
586 error = iqs5xx_write_word(client,
587 prop.swap_x_y ? IQS5XX_X_RES : IQS5XX_Y_RES,
588 max_y);
589 if (error)
590 return error;
591
592 error = input_mt_init_slots(iqs5xx->input, IQS5XX_NUM_CONTACTS,
593 INPUT_MT_DIRECT);
594 if (error)
595 dev_err(&client->dev, "Failed to initialize slots: %d\n",
596 error);
597
598 return error;
599}
600
601static int iqs5xx_dev_init(struct i2c_client *client)
602{
603 struct iqs5xx_private *iqs5xx = i2c_get_clientdata(client);
604 struct iqs5xx_dev_id_info *dev_id_info;
605 int error;
606 u8 val;
607 u8 buf[sizeof(*dev_id_info) + 1];
608
609 error = iqs5xx_read_burst(client, IQS5XX_PROD_NUM,
610 &buf[1], sizeof(*dev_id_info));
611 if (error)
612 return iqs5xx_bl_open(client);
613
614 /*
615 * A000 and B000 devices use 8-bit and 16-bit addressing, respectively.
616 * Querying an A000 device's version information with 16-bit addressing
617 * gives the appearance that the data is shifted by one byte; a nonzero
618 * leading array element suggests this could be the case (in which case
619 * the missing zero is prepended).
620 */
621 buf[0] = 0;
622 dev_id_info = (struct iqs5xx_dev_id_info *)&buf[(buf[1] > 0) ? 0 : 1];
623
624 switch (be16_to_cpu(dev_id_info->prod_num)) {
625 case IQS5XX_PROD_NUM_IQS550:
626 case IQS5XX_PROD_NUM_IQS572:
627 case IQS5XX_PROD_NUM_IQS525:
628 break;
629 default:
630 dev_err(&client->dev, "Unrecognized product number: %u\n",
631 be16_to_cpu(dev_id_info->prod_num));
632 return -EINVAL;
633 }
634
635 switch (be16_to_cpu(dev_id_info->proj_num)) {
636 case IQS5XX_PROJ_NUM_A000:
637 dev_err(&client->dev, "Unsupported project number: %u\n",
638 be16_to_cpu(dev_id_info->proj_num));
639 return iqs5xx_bl_open(client);
640 case IQS5XX_PROJ_NUM_B000:
641 break;
642 default:
643 dev_err(&client->dev, "Unrecognized project number: %u\n",
644 be16_to_cpu(dev_id_info->proj_num));
645 return -EINVAL;
646 }
647
648 if (dev_id_info->major_ver < IQS5XX_MAJOR_VER_MIN) {
649 dev_err(&client->dev, "Unsupported major version: %u\n",
650 dev_id_info->major_ver);
651 return iqs5xx_bl_open(client);
652 }
653
654 switch (dev_id_info->bl_status) {
655 case IQS5XX_BL_STATUS_AVAIL:
656 case IQS5XX_BL_STATUS_NONE:
657 break;
658 default:
659 dev_err(&client->dev,
660 "Unrecognized bootloader status: 0x%02X\n",
661 dev_id_info->bl_status);
662 return -EINVAL;
663 }
664
665 error = iqs5xx_axis_init(client);
666 if (error)
667 return error;
668
669 error = iqs5xx_read_byte(client, IQS5XX_SYS_CFG0, &val);
670 if (error)
671 return error;
672
673 val |= IQS5XX_SETUP_COMPLETE;
674 val &= ~IQS5XX_SW_INPUT_EVENT;
675 error = iqs5xx_write_byte(client, IQS5XX_SYS_CFG0, val);
676 if (error)
677 return error;
678
679 val = IQS5XX_TP_EVENT | IQS5XX_EVENT_MODE;
680 error = iqs5xx_write_byte(client, IQS5XX_SYS_CFG1, val);
681 if (error)
682 return error;
683
684 error = iqs5xx_write_byte(client, IQS5XX_END_COMM, 0);
685 if (error)
686 return error;
687
688 iqs5xx->bl_status = dev_id_info->bl_status;
689
690 /*
691 * Closure of the first communication window that appears following the
692 * release of reset appears to kick off an initialization period during
693 * which further communication is met with clock stretching. The return
694 * from this function is delayed so that further communication attempts
695 * avoid this period.
696 */
697 msleep(100);
698
699 return 0;
700}
701
702static irqreturn_t iqs5xx_irq(int irq, void *data)
703{
704 struct iqs5xx_private *iqs5xx = data;
705 struct iqs5xx_touch_data touch_data[IQS5XX_NUM_CONTACTS];
706 struct i2c_client *client = iqs5xx->client;
707 struct input_dev *input = iqs5xx->input;
708 int error, i;
709
710 /*
711 * This check is purely a precaution, as the device does not assert the
712 * RDY output during bootloader mode. If the device operates outside of
713 * bootloader mode, the input device is guaranteed to be allocated.
714 */
715 if (iqs5xx->bl_status == IQS5XX_BL_STATUS_RESET)
716 return IRQ_NONE;
717
718 error = iqs5xx_read_burst(client, IQS5XX_ABS_X,
719 touch_data, sizeof(touch_data));
720 if (error)
721 return IRQ_NONE;
722
723 for (i = 0; i < ARRAY_SIZE(touch_data); i++) {
724 u16 pressure = be16_to_cpu(touch_data[i].strength);
725
726 input_mt_slot(input, i);
727 if (input_mt_report_slot_state(input, MT_TOOL_FINGER,
728 pressure != 0)) {
729 input_report_abs(input, ABS_MT_POSITION_X,
730 be16_to_cpu(touch_data[i].abs_x));
731 input_report_abs(input, ABS_MT_POSITION_Y,
732 be16_to_cpu(touch_data[i].abs_y));
733 input_report_abs(input, ABS_MT_PRESSURE, pressure);
734 }
735 }
736
737 input_mt_sync_frame(input);
738 input_sync(input);
739
740 error = iqs5xx_write_byte(client, IQS5XX_END_COMM, 0);
741 if (error)
742 return IRQ_NONE;
743
744 /*
745 * Once the communication window is closed, a small delay is added to
746 * ensure the device's RDY output has been deasserted by the time the
747 * interrupt handler returns.
748 */
749 usleep_range(50, 100);
750
751 return IRQ_HANDLED;
752}
753
754static int iqs5xx_fw_file_parse(struct i2c_client *client,
755 const char *fw_file, u8 *pmap)
756{
757 const struct firmware *fw;
758 struct iqs5xx_ihex_rec *rec;
759 size_t pos = 0;
760 int error, i;
761 u16 rec_num = 1;
762 u16 rec_addr;
763 u8 rec_len, rec_type, rec_chksm, chksm;
764 u8 rec_hdr[IQS5XX_REC_HDR_LEN];
765 u8 rec_data[IQS5XX_REC_LEN_MAX];
766
767 /*
768 * Firmware exported from the vendor's configuration tool deviates from
769 * standard ihex as follows: (1) the checksum for records corresponding
770 * to user-exported settings is not recalculated, and (2) an address of
771 * 0xFFFF is used for the EOF record.
772 *
773 * Because the ihex2fw tool tolerates neither (1) nor (2), the slightly
774 * nonstandard ihex firmware is parsed directly by the driver.
775 */
776 error = request_firmware(&fw, fw_file, &client->dev);
777 if (error) {
778 dev_err(&client->dev, "Failed to request firmware %s: %d\n",
779 fw_file, error);
780 return error;
781 }
782
783 do {
784 if (pos + sizeof(*rec) > fw->size) {
785 dev_err(&client->dev, "Insufficient firmware size\n");
786 error = -EINVAL;
787 break;
788 }
789 rec = (struct iqs5xx_ihex_rec *)(fw->data + pos);
790 pos += sizeof(*rec);
791
792 if (rec->start != ':') {
793 dev_err(&client->dev, "Invalid start at record %u\n",
794 rec_num);
795 error = -EINVAL;
796 break;
797 }
798
799 error = hex2bin(rec_hdr, rec->len, sizeof(rec_hdr));
800 if (error) {
801 dev_err(&client->dev, "Invalid header at record %u\n",
802 rec_num);
803 break;
804 }
805
806 rec_len = *rec_hdr;
807 rec_addr = get_unaligned_be16(rec_hdr + sizeof(rec_len));
808 rec_type = *(rec_hdr + sizeof(rec_len) + sizeof(rec_addr));
809
810 if (pos + rec_len * 2 > fw->size) {
811 dev_err(&client->dev, "Insufficient firmware size\n");
812 error = -EINVAL;
813 break;
814 }
815 pos += (rec_len * 2);
816
817 error = hex2bin(rec_data, rec->data, rec_len);
818 if (error) {
819 dev_err(&client->dev, "Invalid data at record %u\n",
820 rec_num);
821 break;
822 }
823
824 error = hex2bin(&rec_chksm,
825 rec->data + rec_len * 2, sizeof(rec_chksm));
826 if (error) {
827 dev_err(&client->dev, "Invalid checksum at record %u\n",
828 rec_num);
829 break;
830 }
831
832 chksm = 0;
833 for (i = 0; i < sizeof(rec_hdr); i++)
834 chksm += rec_hdr[i];
835 for (i = 0; i < rec_len; i++)
836 chksm += rec_data[i];
837 chksm = ~chksm + 1;
838
839 if (chksm != rec_chksm && rec_addr < IQS5XX_CSTM) {
840 dev_err(&client->dev,
841 "Incorrect checksum at record %u\n",
842 rec_num);
843 error = -EINVAL;
844 break;
845 }
846
847 switch (rec_type) {
848 case IQS5XX_REC_TYPE_DATA:
849 if (rec_addr < IQS5XX_CHKSM ||
850 rec_addr > IQS5XX_PMAP_END) {
851 dev_err(&client->dev,
852 "Invalid address at record %u\n",
853 rec_num);
854 error = -EINVAL;
855 } else {
856 memcpy(pmap + rec_addr - IQS5XX_CHKSM,
857 rec_data, rec_len);
858 }
859 break;
860 case IQS5XX_REC_TYPE_EOF:
861 break;
862 default:
863 dev_err(&client->dev, "Invalid type at record %u\n",
864 rec_num);
865 error = -EINVAL;
866 }
867
868 if (error)
869 break;
870
871 rec_num++;
872 while (pos < fw->size) {
873 if (*(fw->data + pos) == ':')
874 break;
875 pos++;
876 }
877 } while (rec_type != IQS5XX_REC_TYPE_EOF);
878
879 release_firmware(fw);
880
881 return error;
882}
883
884static int iqs5xx_fw_file_write(struct i2c_client *client, const char *fw_file)
885{
886 struct iqs5xx_private *iqs5xx = i2c_get_clientdata(client);
887 int error;
888 u8 *pmap;
889
890 if (iqs5xx->bl_status == IQS5XX_BL_STATUS_NONE)
891 return -EPERM;
892
893 pmap = kzalloc(IQS5XX_PMAP_LEN, GFP_KERNEL);
894 if (!pmap)
895 return -ENOMEM;
896
897 error = iqs5xx_fw_file_parse(client, fw_file, pmap);
898 if (error)
899 goto err_kfree;
900
901 mutex_lock(&iqs5xx->lock);
902
903 /*
904 * Disable the interrupt line in case the first attempt(s) to enter the
905 * bootloader don't happen quickly enough, in which case the device may
906 * assert the RDY output until the next attempt.
907 */
908 disable_irq(client->irq);
909
910 iqs5xx->bl_status = IQS5XX_BL_STATUS_RESET;
911
912 error = iqs5xx_bl_cmd(client, IQS5XX_BL_CMD_VER, 0);
913 if (error) {
914 error = iqs5xx_bl_open(client);
915 if (error)
916 goto err_reset;
917 }
918
919 error = iqs5xx_bl_write(client, IQS5XX_CHKSM, pmap, IQS5XX_PMAP_LEN);
920 if (error)
921 goto err_reset;
922
923 error = iqs5xx_bl_cmd(client, IQS5XX_BL_CMD_CRC, 0);
924 if (error)
925 goto err_reset;
926
927 error = iqs5xx_bl_verify(client, IQS5XX_CSTM,
928 pmap + IQS5XX_CHKSM_LEN + IQS5XX_APP_LEN,
929 IQS5XX_CSTM_LEN);
930 if (error)
931 goto err_reset;
932
933 error = iqs5xx_bl_cmd(client, IQS5XX_BL_CMD_EXEC, 0);
934
935err_reset:
936 if (error) {
937 iqs5xx_reset(client);
938 usleep_range(10000, 10100);
939 }
940
941 error = iqs5xx_dev_init(client);
942 if (!error && iqs5xx->bl_status == IQS5XX_BL_STATUS_RESET)
943 error = -EINVAL;
944
945 enable_irq(client->irq);
946
947 mutex_unlock(&iqs5xx->lock);
948
949err_kfree:
950 kfree(pmap);
951
952 return error;
953}
954
955static ssize_t fw_file_store(struct device *dev, struct device_attribute *attr,
956 const char *buf, size_t count)
957{
958 struct iqs5xx_private *iqs5xx = dev_get_drvdata(dev);
959 struct i2c_client *client = iqs5xx->client;
960 size_t len = count;
961 bool input_reg = !iqs5xx->input;
962 char fw_file[IQS5XX_FW_FILE_LEN + 1];
963 int error;
964
965 if (!len)
966 return -EINVAL;
967
968 if (buf[len - 1] == '\n')
969 len--;
970
971 if (len > IQS5XX_FW_FILE_LEN)
972 return -ENAMETOOLONG;
973
974 memcpy(fw_file, buf, len);
975 fw_file[len] = '\0';
976
977 error = iqs5xx_fw_file_write(client, fw_file);
978 if (error)
979 return error;
980
981 /*
982 * If the input device was not allocated already, it is guaranteed to
983 * be allocated by this point and can finally be registered.
984 */
985 if (input_reg) {
986 error = input_register_device(iqs5xx->input);
987 if (error) {
988 dev_err(&client->dev,
989 "Failed to register device: %d\n",
990 error);
991 return error;
992 }
993 }
994
995 return count;
996}
997
998static DEVICE_ATTR_WO(fw_file);
999
1000static struct attribute *iqs5xx_attrs[] = {
1001 &dev_attr_fw_file.attr,
1002 NULL,
1003};
1004
1005static const struct attribute_group iqs5xx_attr_group = {
1006 .attrs = iqs5xx_attrs,
1007};
1008
1009static int __maybe_unused iqs5xx_suspend(struct device *dev)
1010{
1011 struct iqs5xx_private *iqs5xx = dev_get_drvdata(dev);
1012 struct input_dev *input = iqs5xx->input;
1013 int error = 0;
1014
1015 if (!input)
1016 return error;
1017
1018 mutex_lock(&input->mutex);
1019
1020 if (input->users)
1021 error = iqs5xx_set_state(iqs5xx->client, IQS5XX_SUSPEND);
1022
1023 mutex_unlock(&input->mutex);
1024
1025 return error;
1026}
1027
1028static int __maybe_unused iqs5xx_resume(struct device *dev)
1029{
1030 struct iqs5xx_private *iqs5xx = dev_get_drvdata(dev);
1031 struct input_dev *input = iqs5xx->input;
1032 int error = 0;
1033
1034 if (!input)
1035 return error;
1036
1037 mutex_lock(&input->mutex);
1038
1039 if (input->users)
1040 error = iqs5xx_set_state(iqs5xx->client, IQS5XX_RESUME);
1041
1042 mutex_unlock(&input->mutex);
1043
1044 return error;
1045}
1046
1047static SIMPLE_DEV_PM_OPS(iqs5xx_pm, iqs5xx_suspend, iqs5xx_resume);
1048
1049static int iqs5xx_probe(struct i2c_client *client,
1050 const struct i2c_device_id *id)
1051{
1052 struct iqs5xx_private *iqs5xx;
1053 int error;
1054
1055 iqs5xx = devm_kzalloc(&client->dev, sizeof(*iqs5xx), GFP_KERNEL);
1056 if (!iqs5xx)
1057 return -ENOMEM;
1058
1059 i2c_set_clientdata(client, iqs5xx);
1060 iqs5xx->client = client;
1061
1062 iqs5xx->reset_gpio = devm_gpiod_get(&client->dev,
1063 "reset", GPIOD_OUT_LOW);
1064 if (IS_ERR(iqs5xx->reset_gpio)) {
1065 error = PTR_ERR(iqs5xx->reset_gpio);
1066 dev_err(&client->dev, "Failed to request GPIO: %d\n", error);
1067 return error;
1068 }
1069
1070 mutex_init(&iqs5xx->lock);
1071
1072 iqs5xx_reset(client);
1073 usleep_range(10000, 10100);
1074
1075 error = iqs5xx_dev_init(client);
1076 if (error)
1077 return error;
1078
1079 error = devm_request_threaded_irq(&client->dev, client->irq,
1080 NULL, iqs5xx_irq, IRQF_ONESHOT,
1081 client->name, iqs5xx);
1082 if (error) {
1083 dev_err(&client->dev, "Failed to request IRQ: %d\n", error);
1084 return error;
1085 }
1086
1087 error = devm_device_add_group(&client->dev, &iqs5xx_attr_group);
1088 if (error) {
1089 dev_err(&client->dev, "Failed to add attributes: %d\n", error);
1090 return error;
1091 }
1092
1093 if (iqs5xx->input) {
1094 error = input_register_device(iqs5xx->input);
1095 if (error)
1096 dev_err(&client->dev,
1097 "Failed to register device: %d\n",
1098 error);
1099 }
1100
1101 return error;
1102}
1103
1104static const struct i2c_device_id iqs5xx_id[] = {
1105 { "iqs550", 0 },
1106 { "iqs572", 1 },
1107 { "iqs525", 2 },
1108 { }
1109};
1110MODULE_DEVICE_TABLE(i2c, iqs5xx_id);
1111
1112static const struct of_device_id iqs5xx_of_match[] = {
1113 { .compatible = "azoteq,iqs550" },
1114 { .compatible = "azoteq,iqs572" },
1115 { .compatible = "azoteq,iqs525" },
1116 { }
1117};
1118MODULE_DEVICE_TABLE(of, iqs5xx_of_match);
1119
1120static struct i2c_driver iqs5xx_i2c_driver = {
1121 .driver = {
1122 .name = "iqs5xx",
1123 .of_match_table = iqs5xx_of_match,
1124 .pm = &iqs5xx_pm,
1125 },
1126 .id_table = iqs5xx_id,
1127 .probe = iqs5xx_probe,
1128};
1129module_i2c_driver(iqs5xx_i2c_driver);
1130
1131MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
1132MODULE_DESCRIPTION("Azoteq IQS550/572/525 Trackpad/Touchscreen Controller");
1133MODULE_LICENSE("GPL");